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Skin, hair & anti-aging

Melanotan 1

An MC1R-selective melanocortin agonist (also afamelanotide). Tans like Melanotan II, but without its pronounced side effects.

4 min read 12 sources

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Still from the explainer video about this entry
Compound approved · as an implant, EU since 2014Lab tested in the shop

No time to read it all? The video sums up the whole entry in about a minute, from how it works to the studies and storage.

Summary

At a glance

Sources checked on 26 Oct 2026

Main target
1 receptor

MC1R, as an agonist according to ChEMBL. According to the prescribing information the compound binds mainly there12

Half-life when injected
1.7 hours

0.8 to 1.7 hours after injection under the skin, three volunteers4

Eumelanin in the skin
+98 %

Forearm, one week after ten injections over two weeks, seven volunteers5

Pain-free in light (EPP)
69.4 hours

Median after 6 months with the implant, placebo 40.8 hours (US trial)1

Phase 3 in the registry
6 trials

5 of them completed, all with the implant, as of 26 Oct 202611

  • Melanotan 1 is a derivative of the body's own hormone alpha-MSH. As a drug it is called afamelanotide and acts mainly on the MC1 receptor of pigment cells.129
  • As early as 1991 the skin of healthy men tanned after ten injections under the skin, most strongly one to three weeks after the last dose. In a later study the share of dark eumelanin in the forearm rose by 98 percent.35
  • The compound is approved as an implant for the rare light disorder EPP: in the US trial patients stayed pain-free in light for a median of 69.4 hours, 40.8 hours with placebo.1
  • Common side effects in the approval trials were reactions at the implant site and nausea, plus fatigue and darker skin.9
  • The approval covers only the implant for EPP. Everything here describes the state of research, not a recommendation.810
Profile

Updated May 2026

Class
Melanocortin agonist

MC1R-selective, also afamelanotide

Route
Subcutaneous
Half-life
Short

shorter than Melanotan II

Form
Lyophilised powder

reconstituted with BAC water

Sizes
10 mg

1 size in the shop

Contents 16 sections
  1. At a glance
  2. What is Melanotan 1?
  3. How it works
  4. What you need
  5. Reconstitution
  6. Injection
  7. Dosing
  8. What the research shows
  9. Research status
  10. Side effects
  11. Practice
  12. Storage
  13. Related compounds
  14. FAQ
  15. Glossary
  16. Sources

What is Melanotan 1?

Melanotan 1 is an analogue of the body's own hormone alpha-MSH and is also called afamelanotide. Like Melanotan II it acts on the melanocortin pathways, but more selectively: it mainly works on the MC1 receptor, which controls skin pigmentation. It barely acts on the MC4 receptor, through which Melanotan II produces its effects on libido, appetite and nausea.

That is the practical difference: Melanotan 1 tans similarly but brings far fewer side effects. In medicine the substance is even approved as afamelanotide, though there as a slow-release implant. As a research peptide it is injected subcutaneously and dosed in micrograms. It comes as a freeze-dried powder you dissolve in bacteriostatic water.

Comparison

Melanocortin peptides in the lexicon

Which of the two main melanocortin receptors the peptides address according to the TPD lexicon. MC1R controls pigmentation, MC4R in the brain controls appetite and libido. Tap a card to open its entry.

Afamelanotide, mainly MC1R Melanotan 1 MC1R MC4R 1 of 2 melanocortin receptors
Cyclic, several receptors Melanotan II MC1R MC4R 2 of 2 melanocortin receptors Melanocortin agonist, libido PT-141 MC1R MC4R 1 of 2 melanocortin receptors Tripeptide without tanning KPV MC1R MC4R 0 of 2 melanocortin receptors

Simplified: Melanotan II and PT-141 also address further melanocortin receptors. KPV is the end piece of alpha-MSH and acts without these receptors. 129

How it works

Via the MC1 receptor, Melanotan 1 prompts the skin's melanocytes to make more eumelanin. That is the tanning effect, which in a research context is described even with less UV. Because it barely engages the MC4 receptor, the central effects Melanotan II brings are missing: no pronounced nausea surge, no spontaneous erection complex, no strong appetite suppression.

The half-life is short, shorter than Melanotan II. That is why the approved medical form is a depot implant that releases the substance slowly. The injectable research form is used more frequently accordingly. The key point stays: stronger tanning does not mean the skin is protected from UV damage.

Where it acts

Where Melanotan 1 acts

Tap a point or a card. Colour = receptor, grey = effect seen in trials.

  1. Skin (pigment cells)

    More dark eumelanin, the skin tans even without much sun5

    MC1R
  2. Stomach

    Nausea slightly more common than with placebo (19 versus 14 percent)9

    Observed in trials

Targets in the ChEMBL database12

Compound CHEMBL441738: one recorded mechanism, agonist with direct binding to the human receptor.

Melanocortin 1 receptor
Gene
MC1R
UniProt
Q01726
ChEMBL
CHEMBL3795
Action
Agonist, direct binding
Cross-section of skin cells: blue 3D molecules dock on at the top, below them brown pigment granules spread through the cells
Symbolic image.

What you need

Melanotan 1 is used subcutaneously. You need:

Supplies

5 things, numbered as in the picture

Tick off what you already have. Vial and BAC water are our real shop photos at the same size.

Melanotan 1 vial and bacteriostatic water at the same size with the black TPD label, next to two U-100 insulin syringes, two alcohol swabs and a sharps container with a blue lid

  1. Melanotan 1 vial

    The Melanotan 1 vial with the freeze-dried powder

    In the shop

  2. Bacteriostatic water

    Bacteriostatic water to dissolve it

    In the shop

  3. U-100 insulin syringes

    U-100 insulin syringes

    Amazon (opens a new tab)

  4. Alcohol swabs

    Alcohol swabs for the vial cap and the skin

    Amazon (opens a new tab)

  5. Sharps container

    A sealable sharps container for used needles

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Reconstitution

The powder is dissolved in bacteriostatic water. How much water you add sets the concentration and therefore how many units you draw for your dose on the insulin syringe.

Use the peptide calculator for this: pick the water volume to see the concentration and units per dose. Because it is dosed in small microgram amounts, a not-too-high concentration is practical so the units stay easy to read.

When dissolving, just add the bac water, it does not matter if it hits the powder directly. Then swirl or shake until everything has dissolved, both are fine.

Step by step

Dissolving the powder

Four steps, the same for every vial size.

  1. 1Wipe the cap

    Clean the rubber stopper with an alcohol swab.

  2. 2Add BAC water

    Just add it, it does not matter if it hits the powder directly.

  3. 3Swirl or shake

    Until everything has dissolved, both are fine.

  4. 4Draw up

    With the U-100 insulin syringe.

Less water higher concentration fewer units on the syringe Example: 10 mg + 2 ml = 5 mg/ml

Injection

The injection is subcutaneous, into the fat layer under the skin, classically the abdomen (keep about two finger-widths clear of the navel), the front and the inner side of the thigh or the back of the upper arm.

Injection

Where and at what angle

Pick a spot or switch the angle. Subcutaneous means: into the fat layer, not the muscle.

Rotate the spot each time, never the same one twice in a row.

90°More fat under the skin

Rule of thumb: where there is more fat under the skin, insert straight at 90 degrees. In lean people with little fat, 45 degrees, so the needle stays in the fat layer. Simplified diagram.

  1. Clean the spot with an alcohol swab and let it dry

  2. Pinch up a small fold of skin

  3. Insert the needle: at 90 degrees where there is more fat under the skin, at 45 degrees in lean people with little fat

  4. Inject slowly, wait a moment, then withdraw

  5. Put the needle straight into the sharps container

Rotate the site each time.

Dosing

Dosing

Dosing, titration and syringe

Loading the dosing information …

  • Getting started and stepping up, drawn as a staircase
  • Units on the U-100 syringe for every step
  • How long one vial lasts

What the research shows

As afamelanotide, Melanotan 1 is by far the best-studied tanning peptide, because it was approved as a medicine. In an approval study (Langendonk, 2015) the afamelanotide implant increased melanin production and photoprotection in patients with a rare light-sensitivity disease. A long-term observation over 115 patients confirmed a favourable safety profile with mostly mild, transient side effects.

These data come from the medical implant context. For pure tanning use by injection they serve as orientation but are research context. The studies with links are in the source block below.

Study results

What the trials measured

Interactive: switch tabs, tap points, show or hide arms. Arms are named relative to each other, no dosing advice.

Dark pigment (eumelanin) in the skin5

Increase over baseline in percent, one week after ten injections under the skin

Forearm5 Seven volunteers
Melanotan 1 injected 98%
Forehead5 Three volunteers
Melanotan 1 injected 49%

Measured in skin samples before and after the injections, without a comparison group. The light pigment pheomelanin did not change. Very small study with volunteers of skin types III and IV.

Pain-free time in direct sunlight1

Median in hours, two approval trials with the implant

US trial1 After 6 months, 94 participants
Placebo implant 40.8 h
Afamelanotide implant 69.4 h
EU trial1 After 9 months, 74 participants
Placebo implant 0.8 h
Afamelanotide implant 6.0 h

Medians from the abstract. The two trials counted time in light differently and are not directly comparable. In the EU trial there were 77 light reactions with the implant, 146 with placebo.

Repigmented skin after 168 days6

Share in percent, vitiligo, 55 participants

Vitiligo trial6 UV-B light therapy with and without the implant
UV-B light therapy only 33.3%
Implant plus UV-B light therapy 48.6%

Values according to the abstract (33.26 and 48.64 percent). The benefit was clearer in darker skin types (IV to VI), in skin type III there was no significant difference.

Cube of skin layers on a glass plate above a stainless steel cart, with a glowing sphere of light above it in a bright room
Symbolic image.

Research status

Where the research stands

From the first injections in volunteers to approval as an implant: the registered trials with afamelanotide, with status, participants and results. The early studies with injected solution took place before the registry. As of 26 Oct 2026. 11

  1. Preclinical Developed from alpha-MSH, first injections in volunteers
  2. Phase 1 3 trials, 3 completed
  3. Phase 2 9 trials, 9 completed
  4. Phase 3 6 trials, 5 completed
  5. Approval as an implant, EU since 2014
514 participants in phase 3 Planned figures for running trials Approved as an implant under the skin for erythropoietic protoporphyria (EPP): in the EU since 2014, in the USA since October 2019. Not approved for tanning and not as a powder for injection.8
Show all 15 phase 2 and 3 trials on a timelineHide timeline 14 completed 1 running 2 with results
Phase 2
Phase 3

Bar: start to primary endpoint (planned for running trials). Green = completed, blue = progress until 26 Oct 2026. Phase 1: 3 trials on safety and pharmacokinetics, not shown as bars.

Side effects

Melanotan 1 is noticeably better tolerated than Melanotan II, mainly because the MC4 effects are missing. Mostly mild, transient things are reported: slight nausea or headache at the start, injection-site reactions. The spontaneous erection and nausea complex of Melanotan II is practically absent here.

One important difference from Melanotan II: the new or changing moles that are a concern with Melanotan II do not show up the same way with Melanotan 1. The skin tans overall, which is the intended effect. Keeping a general eye on your skin never hurts, though.

Tolerability

Side effects in the approval trials

Out of 100 participants per group, how many had the event up to month 6.

10 of 100 Placebo implant
21 of 100 Afamelanotide implant
Event Placebo implantAfamelanotide implant
Implant site reaction9 10%21%
Nausea9 14%19%
Fatigue9 3%6%
Darker skin9 0%4%

Values from the US prescribing information (125 versus 119 participants). In a long-term observation over up to 8 years with 115 patients there were only mild side effects, mainly nausea.92

Practice

A few things that matter:

  1. Start low, even though Melanotan 1 is milder than Melanotan II.

  2. Be careful with UV

    The tan does not reliably protect against UV damage, so do not overdo sun or tanning beds.

  3. Keep a general eye on your skin, even though the mole changes typical of Melanotan II are not an issue here.

  4. In phases rather than continuously.

Straw hat, a white tube of sunscreen and a glass of water on a light lounger under a blue parasol

Storage

The undissolved powder is robust, normal room temperature (around 20 to 25 degrees) is fine, ideally kept in the dark. The reconstituted solution goes into the fridge (2 to 8 degrees) and stays stable there for at least 4 to 6 months with barely any loss of potency, in practice considerably longer. The bacteriostatic water brings a preservative that keeps the dissolved form stable for longer.

Shelf life

How long it keeps

Undissolved (powder) Room temperature, around 20 to 25 degrees, dark

Robust, no fridge needed. Keeps for several months without trouble.

Dissolved (mixed) Fridge, 2 to 8 degrees

At least 4 to 6 months with barely any loss of potency. The bacteriostatic water brings a preservative.

  • Keep it dark
  • Dissolved: 2 to 8 degrees
  • Note the mixing date on the vial
Nine vials with white powder and blue caps in the door shelf of a bright fridge
Powder dark at room temperature, once dissolved into the fridge (2 to 8 degrees), stable there for at least 4 to 6 months. Symbolic image.

Related

Related compounds

Same receptors, blends with Melanotan 1 or a different path: all in the TPD lexicon.

Melanotan 1
Melanotan 1 Nasal Spray Same compound as a nasal spray Melanotan II Also tans, additionally acts via MC4R Melanotan 2 Nasal Spray Melanotan II as a nasal spray PT-141 Melanocortin agonist focused on libido KPV Same origin (alpha-MSH), without tanning

FAQ

Common questions about Melanotan 1

Short answers, each backed by the sources below.

Is Melanotan 1 approved?

The compound is, but only in one specific form: as an afamelanotide implant under the skin for the rare light disorder erythropoietic protoporphyria (EPP), in the EU since 2014 and in the USA since October 2019. It is not approved for tanning, nor as a powder for injection. The information here describes the state of research and is not a recommendation for use.81012

What do the studies with injected Melanotan 1 show?

The first studies used dissolved compound injected under the skin. In 1991 the skin of 28 healthy men visibly tanned after ten injections over twelve days, in fair and darker skin types alike, most strongly one to three weeks after the last dose. Nothing happened with placebo. A later study measured 98 percent more dark eumelanin in the forearm. Taken by mouth, no compound reached the blood.354

How long does Melanotan 1 act?

The compound itself is broken down quickly: injected, the half-life was 0.8 to 1.7 hours. The tan still lasts longer because the pigment cells keep working. In the study it was still visible three weeks after the last injection. The implant releases the compound slowly, the prescribing information gives a half-life of about 15 hours for it.49

What did the approval trial in EPP show?

In EPP light causes severe pain. In two trials with the implant or a placebo implant patients stayed pain-free longer in direct sunlight: a median of 69.4 versus 40.8 hours in the US trial, 6.0 versus 0.8 hours in the EU trial. The EU trial counted 77 versus 146 light reactions, quality of life improved in both trials.1

Does the tan protect against sunburn?

Not reliably. In a small study with nine healthy adults redness after UV light was somewhat lower six days after the implant, the difference in the sunburn threshold was not significant. That does not replace sun protection. The entry also advises not to overdo sun or tanning beds.7

Which side effects were seen?

In the approval trials mainly reactions at the implant site (21 versus 10 percent) and nausea (19 versus 14 percent), plus fatigue and darker skin. In a long-term observation with 115 patients over up to 8 years side effects stayed mild. In the early injection studies there was occasional stomach upset and facial flushing.924

Glossary

Terms explained briefly

Dotted words in the text open these explanations directly.

Alpha-MSH
Alpha-melanocyte-stimulating hormone: the body's own hormone made of 13 building blocks that triggers tanning of the skin.
EPP
Erythropoietic protoporphyria: a rare inherited disorder in which even brief light causes severe pain in the skin.
Eumelanin
Dark brown pigment of the skin. Unlike the light pheomelanin it makes the skin darker.
Half-life
Time after which only half of a substance is left in the blood.
Implant
A small rod placed under the skin that releases the compound slowly over weeks.
Lyophilisate
Freeze-dried powder. Without water a peptide keeps much longer.
MC1 receptor
Melanocortin 1 receptor on the pigment cells of the skin. When activated, the cells make more dark pigment.
MC4 receptor
Melanocortin 4 receptor, mainly in the brain. It is involved in appetite, libido and erection.
Melanocytes
Pigment cells of the skin. They make melanin and pass it to the surrounding skin cells.
Subcutaneous
Into the fat layer just under the skin.

Evidence

Sources

Show all 12 sourcesHide sources 7 Studies1 Trial registry4 Database checked 26 Oct 2026

Studies

  1. Two approval trials with the implant in EPP

    Langendonk et al., New England Journal of Medicine, 2015

    DOI 10.1056/NEJMoa1411481 PMID 26132941 NCT01605136
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  2. First tanning by injections under the skin, 28 men

    Levine et al., JAMA, 1991

    DOI 10.1001/jama.1991.03470190078033 PMID 1658407
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  3. Tanning and blood levels with three routes of administration

    Ugwu et al., Biopharmaceutics & Drug Disposition, 1997

    DOI 10.1002/(sici)1099-081x(199704)18:3<259::aid-bdd20>3.0.co;2-x PMID 9113347
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  4. More eumelanin in the skin after injections

    Dorr et al., Photochemistry and Photobiology, 2000

    DOI 10.1562/0031-8655(2000)072<0526:ieeati>2.0.co;2 PMID 11045725
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  5. Implant plus UV-B light therapy in vitiligo

    Lim et al., JAMA Dermatology, 2015

    DOI 10.1001/jamadermatol.2014.1875 PMID 25230094 NCT01430195
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  6. Redness and pigment after UV light in healthy adults

    Griffin et al., Photochemical & Photobiological Sciences, 2026

    DOI 10.1007/s43630-026-00986-x PMID 42678656
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  7. Review of pharmacology, studies and EU approval

    Minder et al., Clinical Pharmacokinetics, 2017

    DOI 10.1007/s40262-016-0501-5 PMID 28063031
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed

Trial registry

  1. All trials on ClinicalTrials.gov

    ClinicalTrials.gov, U.S. National Library of Medicine

    Checked 26 Oct 2026 via ClinicalTrials.gov API v2

Database

  1. Long-term observation with 115 patients (PubMed record)

    Biolcati et al., British Journal of Dermatology, 2015 (DOI 10.1111/bjd.13598)

    PMID 25494545
    Checked 26 Oct 2026 via PubMed, doi.org, Crossref
  2. US prescribing information for the implant (side effects, half-life)

    DailyMed, U.S. National Library of Medicine (Stand Mai 2026)

    Checked 26 Oct 2026 via DailyMed
  3. US approval of the implant (NDA 210797, 8 Oct 2019)

    Drugs@FDA, U.S. Food and Drug Administration

    Checked 26 Oct 2026 via openFDA
  4. Mechanism and approval status in ChEMBL

    ChEMBL, EMBL-EBI (CHEMBL441738)

    Checked 26 Oct 2026 via ChEMBL

In the shop

Melanotan 1 in the catalog

Sizes, prices and shipping times are on the product page.

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